. >>> well, while their husbands get set to deliver on the dnc stage, first lady michelle obama and dr. jill biden will help stuff care packages this morning for servicemembers returning from overseas. meanwhile, mrs. obama is getting to be a regular on david letterman's late show. a week after her last appearance, mrs. obama delivered letterman's "top 10 list" last night. the topic? reasons to watch the democratic national convention. take a look. >> as a healthy alternative, we're using low-fat confetti. there will be no kiss cam. >> oh, no, please, come on. >> joe biden says it'll be a big you know what deal. >> wait a minute. >> at long last i'll reveal who i'm voting for. >> well, there you go, ladies and gentlemen. >> the first lady has been on "the late show" four times this year. >> wow! >> she's scheduled to appear on the show again tomorrow night. >> like zsa zsa gabor on the johnny carson show. >>> up next, celebrating maryland's athletes fresh from the olympic games. >>> a new generation of space exploration may be upon us. what engineers in alabama are working on to make m